<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use Illuminate\Http\Request;

class Oss extends Controller
{
    function gmt_iso8601($time)
    {
        return str_replace('+00:00', '.000Z', gmdate('c', $time));
    }

    public function getSign()
    {
        $id = env("OSS_ID");          // 请填写您的AccessKeyId。
        $key = env("OSS_KEY");     // 请填写您的AccessKeySecret。
        // $host的格式为 bucketname.endpoint，请替换为您的真实信息。
        $host = env("OSS_HOST");
        // $callbackUrl为上传回调服务器的URL，请将下面的IP和Port配置为您自己的真实URL信息。
        $callbackUrl = env("OSS_CALLBACKURL");
        $dir = env("OSS_DIR");          // 用户上传文件时指定的前缀。

        $callback_param = array(
            'callbackUrl' => $callbackUrl,
            'callbackBody' => 'filename=${object}&size=${size}&mimeType=${mimeType}&height=${imageInfo.height}&width=${imageInfo.width}',
            'callbackBodyType' => "application/x-www-form-urlencoded"
        );
        $callback_string = json_encode($callback_param);

        $base64_callback_body = base64_encode($callback_string);
        $now = time();
        $expire = 30;  //设置该policy超时时间是10s. 即这个policy过了这个有效时间，将不能访问。
        $end = $now + $expire;
        $expiration = $this->gmt_iso8601($end);


        //最大文件大小.用户可以自己设置
        $condition = array(0 => 'content-length-range', 1 => 0, 2 => 1048576000);
        $conditions[] = $condition;

        // 表示用户上传的数据，必须是以$dir开始，不然上传会失败，这一步不是必须项，只是为了安全起见，防止用户通过policy上传到别人的目录。
        $start = array(0 => 'starts-with', 1 => '$key', 2 => $dir);
        $conditions[] = $start;

        $arr = array('expiration' => $expiration, 'conditions' => $conditions);
        $policy = json_encode($arr);
        $base64_policy = base64_encode($policy);
        $string_to_sign = $base64_policy;
        $signature = base64_encode(hash_hmac('sha1', $string_to_sign, $key, true));

        $response = array();
        $response['accessid'] = $id;
        $response['host'] = $host;
        $response['policy'] = $base64_policy;
        $response['signature'] = $signature;
        $response['expire'] = $end;
        $response['callback'] = $base64_callback_body;
        $response['dir'] = $dir;  // 这个参数是设置用户上传文件时指定的前缀。
        echo json_encode($response);
    }

    public function callBack()
    {
        // 1.获取OSS的签名header和公钥url header
        $authorizationBase64 = "";
        $pubKeyUrlBase64 = "";
        /*
         * 注意：如果要使用HTTP_AUTHORIZATION头，你需要先在apache或者nginx中设置rewrite，以apache为例，修改
         * 配置文件/etc/httpd/conf/httpd.conf(以你的apache安装路径为准)，在DirectoryIndex index.php这行下面增加以下两行
            RewriteEngine On
            RewriteRule .* - [env=HTTP_AUTHORIZATION:%{HTTP:Authorization},last]
         * */
        if (isset($_SERVER['HTTP_AUTHORIZATION'])) {
            $authorizationBase64 = $_SERVER['HTTP_AUTHORIZATION'];
        }
        if (isset($_SERVER['HTTP_X_OSS_PUB_KEY_URL'])) {
            $pubKeyUrlBase64 = $_SERVER['HTTP_X_OSS_PUB_KEY_URL'];
        }

        if ($authorizationBase64 == '' || $pubKeyUrlBase64 == '') {
            header("http/1.1 403 Forbidden");
            exit();
        }

// 2.获取OSS的签名
        $authorization = base64_decode($authorizationBase64);

// 3.获取公钥
        $pubKeyUrl = base64_decode($pubKeyUrlBase64);
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $pubKeyUrl);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 10);
        $pubKey = curl_exec($ch);
        if ($pubKey == "") {
            //header("http/1.1 403 Forbidden");
            exit();
        }

// 4.获取回调body
        $body = file_get_contents('php://input');

// 5.拼接待签名字符串
        $authStr = '';
        $path = $_SERVER['REQUEST_URI'];
        $pos = strpos($path, '?');
        if ($pos === false) {
            $authStr = urldecode($path) . "\n" . $body;
        } else {
            $authStr = urldecode(substr($path, 0, $pos)) . substr($path, $pos, strlen($path) - $pos) . "\n" . $body;
        }

// 6.验证签名
        $ok = openssl_verify($authStr, $authorization, $pubKey, OPENSSL_ALGO_MD5);
        if ($ok == 1) {
            header("Content-Type: application/json");
            $data = array("Status" => "Ok");
            echo json_encode($data);
        } else {
            //header("http/1.1 403 Forbidden");
            exit();
        }
    }
}
